public class Example4_19 {
    public static void main(Strinig args[]) {
        Student zhang = new Student();
	Student geng = new Student();
	zhang.setAge(23);
	System.out.println("zhang的年龄："+zhang.getAge());
	geng.setAge(25);
	System.out.println("geng的年龄:"+geng.getAge());
	}
}
